I don’t think native apps and mobile browser web apps are in opposition. Web-based companies like Google, Twitter, Flickr, and more all have mobile-optimized web sites. They all also have APIs, which can be used for creating platform-specific native apps. 37signals is doing the same thing. Twitter and Gmail are probably the best two examples: great mobile web sites and great native apps. There are a bunch of native clients for 37signals’s services.